POTOK MAKÓWKA KOŁO GRUSZOWA (MAKÓWKA STREAM NEAR GRUSZÓW)



Commune: Fredropol (pow. przemyski, woj. podkarpackie)

Framework element or context represented:
Palaeoenvironment and stratigraphy of marginal deposits in the Eastern Flysh Carpathians.

Primary geological/geomorphological interest:
Olistholites of marls with exotics and shallow water fauna.

Comparative assessment justification:
The site is interesting for the reconstruction process of submarine mudflows in marginal folds of Skole Nappe.

Protection status and accessibility:
Protected as the documentary site of inanimate nature (1995).

Character of site: Natural outcrop.

Area: 0.2 ha

Altitude: 355 m a.s.l.

Lithology: marls

Discipline: Palaeobiology, Palaeoenvironment, Stratigraphy of Phanerozoic

Process Age: Holocene, *all periods

Bedrock Age: Paleogene, Cretaceous, *all periods




Description of primary interest:
The site occurs in the Makówka Stream, flowing along the road to Gruszów and is situated some 400 m upstream from the border of the forest. It is a natural (?) outcrop in the bottom and the left bank of the stream in the form of a steep wall with a length of 30 m and a height of 8 m. In the outcrop, there are currently visible only Baculite Marls (Węgierka Marls) with the general bearings 95/20/N. According to earlier observations, these marls are positioned next to submarine mudflows with exotics, i.e. the Makówka Slump Debris, but at the moment these two rocks are unexposed. The marls of this outcrop occur as an olistholite within the Leszczyny Member /Mbr/ of the Maastrichtian–Early Paleocene age, belonging to the Ropianka Formation, i.e. to the Inoceramian Beds. They are irregularly bedded with an admixture of a silty and sandy material, and disintegrate into thick slabs along poorly visible, horizontal lamination. Shallow-water fauna has been found in the marls studied: ammonites, belemnites, aptychus, bivalves, brachiopods, nautiluses, and others. Ecological analysis of this assemblage indicates the marls to have been deposited in the shelf environment, i.e. in the infraneritic zone connected with an open sea.

Literature:

BURZEWSKI W. 1966–Les marnes à Baculithes sur le fond de la litostratigrphie des couches  à Inocérames dans les Carpathes de “skibas”. (French sum.). Zesz. Nauk. AGH, Geol., 7: 89-115.     GEROCH S., KRYSOWSKA-IWASZKIEWICZ M., MICHALIK M., PROCHAZKA K., RADWAŃSKI Z., UNRUG Z., UNRUG R. & WIECZOREK J. 1979–Sedimantation of Węgierka Marls (Late Senonian, Polish Flysch Carpathians). (English sum.). Rocz. Pol. Tow. Geol.,49/1-2: 105-133.     GONERA M., ALEXANDROWICZ Z. & URBAN J. 2000–Protected areas and objects. In: Alexandrowicz Z. & Poprawa D. (reds) Geodiversity coservation of the Polish Carpathians. (English sum.), Państw. Inst. Geol., Warszawa: 98-108.     KOTLARCZYK J. 1978–Stratigraphy of the Ropianka Formation or of Inoceramian beds in the Skole Unit of the Flysh Carpathians. (English sum.). Prace Geologiczne PAN, 108: 1-82.     KOTLARCZYK J. 1979–Informacja o opisanych w literaturze górnokredowych amonitów z jednostki skolskiej. (Polish only). In: Kotlarczyk J. (red.) Badania Paleontologiczne Karpat Przemyskich. Mat. IV Kraj. Konf. Paleont.: 37-39.     KOTLARCZYK J., KOWALIK J., KRUPA R., MAROSZ J. & RAJCHEL J. 1972–Les nouvelles positions de faune et de flore dans les marnes ŕ Baculithes des Karpates de Przemyśl. (French sum.). Zesz. Nauk. AGH, Geologia, 16: 121-126.     NIEDŹWIEDZKI J. 1876–Spostrzeżenia geologiczne w okolicy Przemyśla. (Polish only). Kosmos,1: 263-268, 317-325.     SZYMAKOWSKA F. 1988–Fauna głowonogów z margli bakulitowych (olistolitów) z Gruszowa, Makówki i Kalwarii Pacławskiej. (Polish only). In: Kotlarczyk J. & Pękala K. (reds) Przewodnik 59 Zjazdu Pol. Tow. Geol. w Przemyślu: 75-77.